Catkin-lint

* Reword include_directories() warning
* Distinguish between warnings and notices

* Be more strict about include paths
* Check if exported libraries are actually libraries
* Check for include()s which should use find_package()
* Add support for upper-case prefix in find_package()

* Read version directly from module
* Fix packaging bug

* Refactor source code
* Add explanation to diagnostic messages
* Fix python installation path

* Improve check of special variables
* Fix rosbuild_compat_fkie usage check
* Use better substitute values for includes and libs

* Do not warn twice about not installed export libraries